Injection devices in diversified embodiments are understood to be in the related art. Such injection devices have a valve element that is able to be operated by an actuator, e.g. a valve needle, which opens an injection hole for an injection and closes it again after the injection. Based on the pressure oscillations in the fuel, occurring in the process, inaccuracies may come about in fuel metering, and undesired noises may appear in addition. The fuel begins to flow out when the valve is opened, so that the pressure in the vicinity of the valve seat drops off. Since the remaining fuel quantity, that is located in the injection device, is first of all still at rest at a higher pressure level, this pressure breakdown continues in the form of a pressure wave upstream, through the fuel supply path. This pressure wave is reflected at cross sectional change locations or projections, and a pressure wave system develops within the valve.
Consequently, based on these pressure oscillations, the pressure gradient between the valve seat and the surroundings, e.g. the intake manifold or the combustion chamber, changes as well, as a function of time. In the case of a fully opened valve this leads to an injection rate that is not constant over time, which impairs the metering accuracy. Furthermore, the pressure oscillations may also have a disadvantageous effect on the geometry of the fuel spray, as well as the diameter of the drops in the spray. In addition, based on the pressure fluctuations in the fuel spray, richer and leaner zones may be created, whereby the combustion and also the exhaust gas behavior may be impaired. Besides the problems with the metering accuracy, the pressure oscillations also lead to undesired noises, and may cause damage to the components, in the long run. From all this, it would be desirable to have an injection device that had the highest requirement on metering accuracy and behavior with respect to noise.